Perilous ice jams

Ice jams on the Red River have been a common problem for decades. Some years the ice fails to wreak havoc. While in other years, such as in 2009, the ice can pile up to cause extensive flooding and damage to homes and infrastructure along the river. The lessons of the past are a reminder that dangerous ice jams can arise during any spring thaw.

Since neither the municipalities north of Winnipeg and the provincial government want a repeat of 2009, there are three 22-tonne Amphibex machines now focusing on areas of the Red River that are historically prone to ice jamming. The Amphibex AE 400 ice-breaking machines began their work where the Red meets Netley Creek and are now headed southward. The three machines are proceeded by seven ice-cutting machines that weakened the ice, enabling the Amphibexes to break the ice in advance of the spring thaw, reducing the likelihood of ice jams.

Manitoba Premier Greg Selinger said that new electronic equipment will assist with more precise targeting of ice-cutting and breaking efforts. Seven global position systems (GPS) have been installed on the ice cutters to track in real time exactly where the cuts have been made.

As well, ground-penetrating radar (GPR) is being used to determine the thickness of the ice on sections of the Red River. The information will feed into an ice-jam computer-based model to help optimize ice-jam prevention measures. An ice-jam prediction model based on satellite imagery will also be tested. Both models are being developed in collaboration with the Canada Centre for Remote Sensing and Environment Canada.

As the GPR is towed across the ice, the internal transmitter sends pulses of radio frequency waves into the ice. The pulse reflects or “pings” to the bottom of the ice and sends the signal back to the receiver allowing the operator to accurately measure the thickness of the ice.

GPR has been used mainly on the Red River, but also on the Portage Diversion and Assiniboine River.

The provincial ice-mitigation fleet consists of two Amphibex AE 400 ice-breaking machines, seven ice-cutting machines, and six amphibious transport and support vehicles. North Red Community Water Maintenance Inc., a tri-municipal organization, owns a third Amphibex and manages, maintains and deploys the equipment for the province.

Manitoba is also investing in multi-year programs in the north Red River area that will result in greater flood protection, said the premier. The $9.8-million Manitoba Individual Flood Proofing Initiative provides funding for protection of individual homes and businesses. Communities also have access to the $15.6-million Canada-Manitoba 2010 Community Flood Protection Program.

In January, the province announced almost $22 million in additional equipment and resources to support flood fighting and preparedness. including additional sandbag machines, sandbags, portable diking systems, flood barriers, pumps and steamers. These investments supplement the significant existing inventory of provincial and municipal flood-fighting equipment already available to protect homes, businesses and communities across the province.

The new investments in flood protection along the Red would have come in handy when arguably the worst ice-jam disaster occurred in Winnipeg’s history.

On April 15, 1882, Winnipeggers flocked to witness the grand opening of the new 900-foot Broadway Bridge that linked Winnipeg to St. Boniface (it has since been replaced by the Provencher Bridge). At the time, Broadway didn’t end at Main Street, but reached the foot of the Red River. Prior to the completion of the bridge, Broadway was linked to Provencher Avenue by a ferry in the summer, and people ventured out over the ice at their own peril during the winter to make the crossing.

“Residents who have witnessed the opening of former springs here, greatly admired the contrast, and those who experienced it (as) it used to be to get to and from St. Boniface by means of boats, planks, ice, etc. at the imminent risk of their lives, contemplated the improvement with lively satisfaction,” reported the Manitoba Free Press. “A gentleman who has been in a position to know the facts says that ... this has been the first spring in 10 years in which there have not been some drowning accidents on the Red River during the breaking up of the ice.”

Others on the scene commented on the strength of the bridge, predicting it would easy withstand the onslaught of the coming spring ice break-up. But two days later news arrived of a large ice jam sweeping away the Emerson Bridge. Still, people believed Winnipeg would escape the worst Mother Nature could hurl their way. A voice of warning came from the Free Press, which cautioned that the “ice remained motionless — a rugged, sinister area, picturesque but terrible. From bank to bank,up and down the river for miles was one vast plain of grinding, troubling ice.”

A 1:15 p.m. on April 19 — just four days after the grand opening — the bridge began to swing and sway with the impact of a massive ice jam. As a result of its unwieldy motion, one and then two spans plunged into the river and traveled downstream riding on the ice at a rate estimated at six mph.

The first span disappeared around a bend in the river “with the second in hot pursuit, but people at the foot of McWilliam Street (now Pacific) saw only one span pass there, so it was supposed that the other slipped off the ice and lies at the bottom of the river ...”

The Broadway Bridge suffered another indignity when the steamer Victoria broke away from its moorings and struck the bridge’s second pier. Fortunately, the steamer remained long enough in place before being swept away by the ice for passengers aboard to scramble onto the remaining portions of the bridge and from there to safety.

Shanty Town on Hudson’s Bay land along the bank of the Red was inundated, and water advanced up Notre Dame, which at the time ended at the foot of the Red. In St. Boniface, similar flooding took place.

Unlike today, Winnipeggers had few weapons at their disposal to combat nature’s fury. In 1882, the city dispatched men to “dynamite” the ice jams. At St. John’s three kegs of black powder were used to break up one ice jam.

After the calamity, the bridge was rebuilt and city life went on, but each spring residents kept a more wary eye on the ice building up on the Red River.

Today, ice-cutters and the three Amphibex machines are a more trustworthy method of preventing ice-jams, but there is always the lingering anxiety that the forces of nature can at any time overwhelm the best-laid plans, repeating incidents similar to those in 1882 and 2009.